Capturing the energy of Formula 1 racing in its iconic form, the 251 foot tall Observation Tower provides a dramatic focal point for the Circuit of the Americas and a new landmark for central Texas. Conceived as a visual finale to the central Grand Plaza, the Tower also serves as a memorable backdrop to the Austin360 Amphitheater concert venue at its base. The structure’s unique design anchors visitors’ experience of the motorsports and entertainment complex and fosters a sense of place that is essential to the new circuit’s identity.
The construction of the Observation Tower represents the successful integration of material efficiency with thoughtful structural design and elegant aesthetics. The Tower’s primary structure consists of a continuously-welded double-helix stair wrapped in a filigree-like diagrid. Each stair run serves as a helical diaphragm that transfers loads to a layered perimeter of vertical and diagonal HSS tubes. These small, distributed members contribute the necessary overall strength by number rather than individual brawn, enhancing the feeling of lightness and verticality that the Tower embodies. Together, the stair stringers/diaphragm, diagonal HSS layer and vertical HSS layer form a fully-braced tube.
Like Formula 1 racecars, the form of the Tower is directly influenced by its performance. Inspired by the image of red streaks of glowing light that tail lights leave behind in the dark, a roof of red steel tubes fans out over the amphitheater stage, converging at the base of the Tower to form a “veil” that sweeps up and over the central elevator core. The 8” diameter tubes not only have a strong visual impact, but also contribute to the structural stability of the Tower by acting as an outrigger column for lateral load resistance via a series of struts and rods that tie back to the primary structure.
Seemingly suspended from the red pipe steel canopy is a 900 square foot viewing deck that offers a sweeping panorama of the entire track, downtown Austin, and the nearby Hill Country from an elevation of 230 feet. A portion of the floor is structural laminated glass, allowing more daring visitors to look straight down to the ground below their feet. To reach the viewing deck, visitors can either ride a high-speed elevator or climb up 428 steps to their destination. At night, the stairs are illuminated by LED lights capable of producing an unlimited number of color combinations.
With less than a year to complete the venue in time for the inaugural race, final engineering, fabrication and erection of the Tower had to occur inside an extremely compressed timeframe. In order to expedite completion, the architectural, structural, and fabrication teams coordinated design solutions, detailing and construction strategies via a fully-connected 3D model instead of traditional paper drawings. This method allowed for agile, efficient communication between teams, and the project’s general contractor has estimated that it saved three months over traditional delivery methods.
In both its design and construction, the Observation Tower embodies the sense of precision, lightness and sleek dynamism associated with racing. Evoking the notion of split-second speed, the landmark structure reflects the spirit of the Circuit of the Americas and serves to establish the emerging identity of the complex as a world-class recreation and entertainment destination.
About Circuit of the Americas
Circuit of the Americas is the first purpose-built Formula 1 racing facility in the United States, playing host to the inaugural U.S. Grand Prix on November 18, 2012. Built around a 3.4-mile course designed by Tilke GmbH, the facility holds 120,000 spectators and is also home to the MotoGP, V8 Supercar, and American LeMans series starting in 2013. Beyond the racetrack itself, this motor sports and entertainment destination consists of more than a dozen buildings, bridges, and other structures.
